Placement of implants in the mandible reconstructed with free vascularized fibula flap: comparison of 2 cases Mehmet Kürkcü, DDS, MSc, PhD, a Mehmet Emre Benlidayı, DDS, b Cem Kurtoğlu, DDS, PhD, c and Erol Kesiktaş, MD, d Adana, Turkey FACULTY OF DENTISTRY, CUKUROVA UNIVERSITY The reconstruction of mandibular continuity defects after tumor resection with free vascularized bone flaps is considered to be a treatment option. Although the fibula flap presents many advantages, it does not offer sufficient bone height to restore the alveolar arch when reconstruction involves a dentate mandible. In this report, 2 patients who were referred to our clinic with reconstructed mandibles with diagnosis of amelablastoma are presented and compared. The mandibles of these patients were reconstructed with free vascularized fibula flaps. Whereas one of the reconstructed mandibles was vertically distracted before implant placement, distraction procedure was not carried out for the other patient. Increasing height of the fibula flap by distraction osteogenesis before implant placement in dentate mandible is desirable from a functional and esthetic point of view. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105:e36-e40) Mandibular bone resection because of neoplasia can cause extensive defects including bone, oral mucosa, muscles, and teeth. Reconstruction of the maxillofacial region has been a challenge owing to the complexity of function and esthetics. The reconstruction of mandibular continuity defects following tumor resection with free vascularized bone flaps is considered to be a treatment option. 1 Different donor sites, such as the iliac crest, the fibula, the scapula, and the radius, have been recommended recently, with predictable long-term results. 2-5 Each technique has its specific advantages and disadvantages. The radius and the iliac crest have limited length. 6 On the other hand, the scapula has limited width. 6 The free vascularized fibula flap was first used by Hidalgo in 1989 for reconstruction of the continuity mandibular defects. 7 The fibula flap presents many advantages, such as sufficient length of the bony segment, good vascularization, better quality of the bone, long vascular pedicle, and proper dimension for implant placement. 8-10 However, the fibula does not offer a Assistant Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Cukurova University. b Resident, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Cukurova University. c Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Cukurova University. d Assistant Professor, Department of Plastic and Reconstructive Surgery, Faculty of Dentistry, Cukurova University. Received for publication Jun 27, 2007; returned for revision Aug 22, 2007; accepted for publication Sep 24, 2007. 1079-2104/$ - see front matter 2008 Mosby, Inc. All rights reserved. doi:10.1016/j.tripleo.2007.09.023 sufficient bone height to restore the alveolar arch when reconstruction involves a dentate mandible. This situation may create a significant difference in the level of the alveolar crest between the residual mandible and the reconstructed part, thus causing functional and esthetic problems. 11 In the present report, 2 patients who were referred to our clinic with a diagnosis of amelablastoma are presented and the treatment outcomes compared. The mandibles of these patients were reconstructed with free vascularized fibula flaps. Whereas one of the reconstructed mandibles was vertically distracted before implant placement, distraction procedure was not carried out for the other patient. CASE 1 A 42-year-old female patient who had an ameloblastoma (Fig. 1) on the right side of the mandible was reconstructed by using free vascularized fibula flap after resection. Panoramic radiograph showed wellintegrated fibula flap after 18 months (Fig. 2). Implant placement was planned in the reconstructed area. From a prosthetic point of view, there was a significant increase in the vertical intermaxillary distance because of the insufficient height of the fibula, which could jeopardize the long-term success of implants. Vertical distraction osteogenesis of the reconstructed mandible was planned to increase the height of the fibula flap. However, the patient did not accept this treatment choice, because of further surgery. The risks and lower longterm success rate of implant placement without increasing the height of fibula were explained to the patient. Three SLA ITI implants (Straumann, Waldenburg, Switzerland) 4.1 mm in diameter and 12 mm in length e36
Volume 105, Number 3 Kurkcu et al. e37 Fig. 1. Orthopantomogram showing ameloblastoma on the right side of the mandible. Fig. 2. Reconstruction of the mandible with free vascularized fibula flap. Fig. 3. A, Clinical view of the implant-supported prostheses. B, Orthopantomogram showing prosthetic rehabilitation with the implant-supported prostheses in the reconstructed mandible. were placed into the reconstructed mandible under local anesthesia. Primary stability of all implants was achieved. The healing period was uneventful. Prosthetic rehabilitation was performed after an osseointegration period of 3 months (Fig. 3). However, there was a vertical discrepancy between the reconstructed mandible and the dentate mandible on the unaffected site, which was expected. The patient was followed-up for 3 years. CASE 2 A 41-year-old female patient who had an ameloblastoma on the right side of the mandible was reconstructed by using free vascularized fibula flap after resection. Panoramic radiograph showed well integrated fibula flap after 12 months (Fig. 4). Implant placement was planned in the reconstructed area. However, there was a vertical discrepancy between fibula and the unaffected dentate side because of insufficient height of the fibula, which could jeopardize the longterm success of implants. For this reason, vertical distraction osteogenesis of the reconstructed mandible was Fig. 4. Reconstruction of the mandible with free vascularized fibula flap. planned to increase the height of the fibula flap before implant placement. The procedure was performed under local anesthesia. The fibula flap was approached via a vestibular incision, taking care to preserve lingual mucoperiosteal attachment. The bidirectional vertical intraoral alveolar distractor (Modus ARS 1.5; Medartis, Basel, Switzerland) was positioned on the vestibular bony surface. Adjustment of the distractor was performed before
e38 Kurkcu et al. March 2008 Fig. 6. Orthopantomogram showing formation of the callus between bone segments at the end of the consolidation period. Fig. 5. A, Placement of the bidirectional distractor in the reconstructed mandible. B, Radiologic view of the distractor. starting the osteotomy. A box-shaped osteotomy was done using a sagittal saw and osteotomes on the vestibular aspect of the reconstructed mandible, and the green stick fracture was achieved on the lingual side with chisels. The distractor was then applied, fixed, and temporarily activated to test for movement of the distracted segment (Fig. 5). Subsequently, the distracted segment was repositioned to its initial position and then the surgical incision was closed, leaving part of the distractor passing through the incision. After 7 days of latency period, activation of the distractor started at 1 mm per day, using a frequency of 0.5 mm distraction every 12 h. The bone was distracted by about 10 mm. The distractor was then maintained in position passively for 3 months to allow consolidation of neocallus formed between the 2 bone segments during distraction (Fig. 6). No complications were encountered during the healing process. There was no relevant vertical discrepancy between the reconstructed mandible and the dentate mandible on the unaffected site clinically after consolidation period. Impressions were taken to prepare a surgical stent with holes for ideal implant placement. The distractor was removed under local anesthesia, and newly generated bone in the distracted area was observed clinically. After the device removal, 3 endosseous implants (Aesthetica Euroteknika, Sallanches, France) 4.1 mm in diameter and 12 mm in length were placed into the distracted area (Fig. 7). Primary stability was achieved for all implants. The postoperative period was uneventful. Prosthetic rehabilitation was performed successfully after 3 months of osseointegration period (Fig. 8). The patient had no complaints after 1 year of follow-up. DISCUSSION Microsurgical techniques are now considered to be safe and reliable in reconstruction of the jaws after tumor resection. 12 Among the different flaps used for mandibular reconstruction, the fibula flap has many advantages compared with other vascularized bone flaps, such as the iliac crest and the scapula. 13 The main disadvantage of fibula flap is the insufficient bone height for the reconstruction of both the skeletal base and the alveolar ridge. This is especially evident in cases of partial loss of dentate mandibles. 12 In these cases, despite a successful reconstruction with fibula flap, a relevant vertical discrepancy between the reconstructed side and unaffected dentate mandible may be present. In treating this discrepancy, fixed or removable implant-supported prosthetic rehabilitation may be used. Psychologic and anatomic needs and desires of the patients are important factors on determining the type of prosthesis. Removable prostheses are based on the amount of support for the restoration, as in traditional tooth-supported restorations, and hygiene control may be easier. But fixed prostheses have less food entrapment and maintenance, and, especially, patients with these kinds of restorations think they feel more like natural teeth. Therefore, fixed prostheses that satisfied the patients goals and eliminated the vertical discrepancy were used in both cases. From a functional point of view, the implants need to support long crowns to reach the occlusal plane, with the risk of unfavorable bending moments and implant
Volume 105, Number 3 Kurkcu et al. e39 Fig. 7. Placement of the implants into the distracted area. Fig. 8. A, Clinical view of the implant-supported prostheses. B, Orthopantomogram showing prostethic rehabilitation with the implant-supported prostheses in the distracted mandible. overload, which could jeopardize long-term implant survival. 14 In an earlier study, it was stated that for every 1 mm of crown height increase, the force increase may be 20%. 15 Also, long prosthetic superstructures are unacceptable from an esthetic point of view. There are different methods to increase the height of the fibula flap. The fibula flap can be placed at the level of unaffected dentate mandible, which effects facial contour negatively. Alternatively, the fibula doublebarrel technique can overcome this problem. 16 However, in the case of large defects, the length of the bone segment may not be enough for duplication of the entire reconstructed part. The other treatment option to increase the height of the fibula flap is using a new revascularized flap or autogenous onlay bone graft. 11 However, this solution is not accepted by patients, because of further major surgery and morbidity. The ideal treatment option including vertical distraction osteogenesis of fibula flap and then implant placement were proposed to our patients for better prosthetic rehabilitation of reconstructed mandible. In both cases, the same size and number of implants were used regardless of whether the graft was distracted or not. Although the first patient wished to undergo implant placement, she did not accept the distraction osteogenesis and other procedures to increase the insufficient height of fibula because of further surgical operation. For this reason, we placed implants into the reconstructed mandible without increasing the vertical height of the fibula and informed the patient about the risks of this treatment. Finally, the esthetic result was not acceptable, because of the significant difference in the level of the alveolar crest between the residual mandible and the reconstructed part (Fig. 3, A). Although there was no evident bone loss around the implants in our first case, bone resorption may be expected owing to bending moments and implant overload due to long prosthetic superstructures. 14 In addition, there were some periodontal problems, including insufficient sulcus depth and less attached mucosa. Owing to this unfavorable periodontal status, the patient can not clean the implants effectively and she has to be followed up frequently. On the other hand, the second case had no complaint after 1 year of implant loading. There was no bone resorption around implants, periodontal tissues were healthy, and the esthetic result was acceptable. Consequently, better esthetic and functional prosthetic rehabilitation with implants was achieved in the second case compared with the first case (Figs. 3, A, and 8, A). This method avoids the requirement of a second major reconstructive procedure, such as new revascularized flap and onlay autologous bone graft fixed on the top of the reconstructed mandible. Furthermore, distraction histogenesis of the soft tissue surrounding the mandible is achieved and adapted the new situation of the distracted bone. In conclusion, comparison of these 2 cases reveals that increasing height of the fibula flap with distraction osteogenesis before implant placement is desirable from a functional and an esthetic point of view. REFERENCES 1. Foster RD, Anthony JP, Sharma A, Pogrel MA. Vascularized bone flaps versus nonvascularized bone grafts for mandibular
e40 Kurkcu et al. March 2008 reconstruction: an outcome analysis of primary bony union and endosseous implant success. Head Neck 1999;21:66-71. 2. Taylor GI. Reconstruction of the mandible with free composite iliac bone grafts. Ann Plast Surg 1982;9:361-76. 3. Hidalgo DA, Recow A. A review of 60 consecutive fibula free flap mandible reconstruction. Plast Reconstr Surg 1982;96: 585-96. 4. Swartz WM, Banis JC, Newton ED, Ramasastry SS, Jones NF, Acland R. The osteocutaneous scapular flap for mandibular and maxillary reconstruction. Plast Reconstr Surg 1986;77:530-45. 5. Swanson E, Boyd JB, Manktelow RT. The radial forearm flap: reconstructive applications and donor site defects in 35 consecutive patients. Plast Reconstr Surg 1990;85:258-66. 6. Helman JI, Blanchaert RH Jr. Microvascular free tissue transfer. In: Miloro M, Ghali GE, Larsen PE, Waite PD, editors. Peterson s principles of oral and maxillofacial surgery. London: Decker; 2004. p. 803-19. 7. Hidalgo DA. Fibula free flap: a new method of mandible reconstruction. Plast Reconstr Surg 1989;84:71-9. 8. Frodel J, Funk GF, Capper DT, Fridrich KL, Blumer J, Haller JR, Hoffman HT. Osteointegrated implants: a comparative study of bone thickness in four vascularized bone flaps. Plast Reconstr Surg 1993;92:449-55. 9. Moscoso JF, Keller J, Genden E, Weinberg H, Biller HF, Buchbinder B, et al. Vascularized bone flaps in oromandibular reconstruction. A comparative anatomic study of bone stock from various donor sites to assess suitability for endosseous dental implants. Arch Otolaryngol Head Neck Surg 1994;120:36-43. 10. Yim KK, Wei FC. Fibula osteoseptocutaneous flap for mandible reconstruction. Microsurgery 1994;15:245-49. 11. Chiapasco M, Brusati R, Galioto S. Distraction osteogenesis of a fibular revascularized flap for ımprovement of oral implant positioning in a tumor patient: a case report. J Oral Maxillofac Surg 2000;58:1434-40. 12. Nocini PF, Wangerin K, Albanese M, Kretschmer W, Cortelazzi R. Vertical distraction of a free vascularized fibula flap in a reconstructed hemimandible: case report. J Craniomaxillofac Surg 2000;28:20-4. 13. Reychler H, Iriarte Ortabe J, Pecheur A, Brogniez V. Mandibular reconstruction with a free vascularized fibula flap and osseointegrated implants: a report of four cases. J Oral Maxillofac Surg 1996;54:1464-9. 14. Misch CE. Force factors related to patient conditions. In: Misch CE, editor. Dental implant prosthetics. St. Louis: Mosby; 2005. p. 91-104. 15. Misch CE, Bidez MW. Implant protected occlusion: a biomechanical rationale. Compend Contin Educ Dent 1994;15:1330-42. 16. Bahr W, Stoll P, Wachter R: Use of the double barrel free vascularized fibula in mandibular reconstruction. J Oral Maxillofac Surg 1998;56:38-44. Reprint requests: M. Emre Benlıdayı, DDS Cukurova Universitesi Dis Hekimligi Fakultesi Agiz Dis Cene Hastaliklari ve Cerrahisi Anabilim Dali 01330 Balcali/Yuregir Adana Turkey ebenlidayi@cu.edu.tr